This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 18 |
| 3 | 1348 |
| 4 | 264168 |
| 5 | 107059696 |
| 6 | 77812181280 |
| 7 | 92178659860288 |
| 8 | 166177428088123008 |
| 9 | 432941319641569590016 |
| 10 | 1565619431839802755158528 |
| 11 | 7608371278068863387781342208 |
| 12 | 48386147164823804551330131929088 |